The present invention relates to a device for measuring the intensity of a strong current passing through a wire.
The term “strong current” is used to mean any current with an intensity between 100 and 1000 A.
To measure such strong currents, it is normally the magnetic field generated around the wire conducting the current that is measured.
To obtain an accurate measurement of this magnetic field, a so-called “opposition” method is used.
This method consists in placing around the wire a winding conducting a current counter to the direction of the magnetic field, that is adjusted to cancel the magnetic field.
When the counter-current control loop is a system said to be sampled at a frequency F0, the components having frequencies greater than the frequency F0 that are present in the current to be measured can create serious errors.